title: Ultrasensitive impedimetric lectin biosensors with efficient antifouling properties applied in glycoprofiling of human serum samples.
abstract: Ultrasensitive impedimetric lectin biosensors recognizing different glycan entities on serum glycoproteins were constructed. Lectins were immobilized on a novel mixed self-assembled monolayer containing 11-mercaptoundecanoic acid for covalent immobilization of lectins and betaine terminated thiol to resist nonspecific interactions. Construction of biosensors based on Concanavalin A (Con A), Sambucus nigra agglutinin type I (SNA), and Ricinus communis agglutinin (RCA) on polycrystalline gold electrodes was optimized and characterized with a battery of tools including electrochemical impedance spectroscopy, various electrochemical techniques, quartz crystal microbalance (QCM), Fourier transform infrared (FT-IR) spectroscopy, atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS) and compared with a protein/lectin microarray. The lectin biosensors were able to detect glycoproteins from 1 fM (Con A), 10 fM (Ricinus communis agglutinin (RCA), or 100 fM (SNA) with a linear range spanning 6 (SNA), 7 (RCA), or 8 (Con A) orders of magnitude. Furthermore, a detection limit for the Con A biosensor down to 1 aM was achieved in a sandwich configuration. A nonspecific binding of proteins for the Con A biosensor was only 6.1% (probed with an oxidized invertase) of the signal toward its analyte invertase and a negligible nonspecific interaction of the Con A biosensor was observed in diluted human sera (1000×), as well. The performance of the lectin biosensors was finally tested by glycoprofiling of human serum samples from healthy individuals and those having rheumatoid arthritis, which resulted in a distinct glycan pattern between these two groups.
authors.affiliation: Department of Glycobiotechnology, Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovak Republic.
authors.forename: Tomas
authors.initials: T
authors.lastname: Bertok
authors.forename: Ludmila
authors.initials: L
authors.lastname: Klukova
authors.forename: Alena
authors.initials: A
authors.lastname: Sediva
authors.forename: Peter
authors.initials: P
authors.lastname: Kasák
authors.forename: Vladislav
authors.initials: V
authors.lastname: Semak
authors.forename: Matej
authors.initials: M
authors.lastname: Micusik
authors.forename: Maria
authors.initials: M
authors.lastname: Omastova
authors.forename: Lucia
authors.initials: L
authors.lastname: Chovanová
authors.forename: Miroslav
authors.initials: M
authors.lastname: Vlček
authors.forename: Richard
authors.initials: R
authors.lastname: Imrich
authors.forename: Alica
authors.initials: A
authors.lastname: Vikartovska
authors.forename: Jan
authors.initials: J
authors.lastname: Tkac
mesh_terms: D057219:Biofouling / Q000517:prevention & control*; D015374:Biosensing Techniques / Q000379:methods*; D006023:Glycoproteins / Q000097:blood* / Q000737:chemistry / Q000378:metabolism; D006046:Gold / Q000737:chemistry; D006801:Humans; D018625:Microscopy, Atomic Force; D008958:Models, Molecular; D037121:Plant Lectins / Q000378:metabolism*; D011487:Protein Conformation; D058525:Quartz Crystal Microbalance Techniques; D013499:Surface Properties
chemical_list: D006023:Glycoproteins; D037121:Plant Lectins; D006046:Gold